The present invention relates to an apparatus and a method for erasing data from an optical disk.
A CD-R disk is a typical write-once optical disk, and a user can write data on the CD-R disk only once. However, when the data on the CD-R disk becomes unnecessary, it is not easy to erase the written data from the CD-R disk. Therefore, the CD-R disk is rendered unplayable by using a disposal method, such as artificially applying a stress to the disk (folding, breaking, or damaging the disk) or changing the media characteristics under high temperature condition, whereby secret information recorded on the disk is prevented from leaking.
However, the conventional data erasing method relating to the write-once optical disk has the following drawbacks.
1) Reliability is insufficient, that is, it is uncertain whether the disk is completely unplayable or not.
2) The cost is high.
3) Erasing of data limited to a specific recording area cannot be carried out.
4) Substances detrimental to the environment are released.
It is expected that the CD-R disk market will become widespread in the future and, therefore, development of a simple and low-cost method and apparatus for completely erasing recorded data from the CD-R disk has been desired.
The present invention is made to solve the above-described problems and has for its object to provide an apparatus and a method for completely erasing recorded data from write-once optical disks.
Other objects and advantages of the invention will become apparent from the detailed description that follows. The detailed description and specific embodiments described are provided only for illustration since various additions and modifications within the scope of the invention will be apparent to those of skill in the art from the detailed description.
According to a first aspect of the present invention, there is provided an optical disk data erasing apparatus which is an optical disk recording apparatus for writing or reading data in/from a recordable optical disk by irradiating the optical disk with a laser beam, the optical disk recording apparatus being connected to a host computer through an interface bus. The optical disk data erasing apparatus comprises: a judgement means for judging as to whether a loaded optical disk is a write-once optical disk or not; an instruction recognition means for recognizing an instruction from the host computer; and an erasing means for executing a data erasing process on the basis of the instruction; wherein the erasing means overwrites the optical disk which is judged as a write-once optical disk by the judgement means, by irradiating the optical disk with a laser beam having the same recording power as that at recording, thereby erasing data recorded on the optical disk. Therefore, an optical disk data erasing apparatus which is able to completely erase data on an optical disk is easily realized at low cost, without having to use a special apparatus, and without generating substances detrimental to environment, whereby leakage of secret information can be prevented when the optical disk is discarded.
According to a second aspect of the present invention, there is provided an optical disk data erasing apparatus which is an optical disk recording apparatus for writing or reading data in/from a recordable optical disk by irradiating the optical disk with a laser beam, the optical disk recording apparatus being connected to a host computer through an interface bus. The optical disk data erasing apparatus comprises: a judgement means for making a judgement as to whether a loaded optical disk is a write-once optical disk or not; an instruction recognition means for recognizing an instruction from the host computer; and an erasing means for executing a data erasing process on the basis of the instruction; wherein the erasing means overwrites the optical disk which is judged as a write-once optical disk by the judgement means, by irradiating the optical disk with a laser beam having a recording power higher than that at recording, thereby erasing data recorded on the optical disk. Therefore, an optical disk data erasing apparatus which is able to completely erase data on an optical disk is easily realized at low cost, without having to use a special apparatus, without generating substances detrimental to environment, whereby leakage of secret information can be prevented when the optical disk is discarded.
According to a third aspect of the present invention, the optical disk data erasing apparatus according to the first or second aspect further comprises a disk recording information acquisition means for acquiring disk recording information relating to a data-recorded area or a data-unrecorded area of the write-once optical disk, on the basis of a disk recording information acquisition instruction which is issued by the host computer; wherein the erasing means erases data recorded in the data-recorded area. Therefore, the data erasing process can be performed on only the data-recorded area, while the data-unrecorded area, which needs not be erased, is outside the target of the erasing process, whereby the time required for the erasing process is reduced.
According to a fourth aspect of the present invention, the optical disk data erasing apparatus according to the third aspect further comprises a determination means for determining whether data are recorded on the write-once optical disk or not, on the basis of the disk recording information which is obtained by the disk recording information acquisition means; wherein, when data are recorded on the write-once optical disk, the erasing means executes the recorded-data erasing process; and when no data are recorded on the optical disk, the determination means returns an error signal to the host computer to notify the user that the data erasing process is not going to be executed. Therefore, when no data are recorded on the optical disk, the user can know that there is no need to execute the data erasing process on the disk, whereby the user can perform the erasing process on only a data-recorded optical disk, without performing an unnecessary erasing process.
According to a fifth aspect of the present invention, the optical disk data erasing apparatus according to the third aspect further comprises: a notification means for notifying the user of the disk recording information which is obtained by the disk recording information acquisition means, through the host computer; and an erasing area detection means for detecting, when an instruction which specifies a data erasing area is issued from the user through the host computer on the basis of the disk recording information, an area corresponding to the specified data erasing area on the basis of the instruction; wherein the erasing means erases the data recorded in the erasing area which is detected by the erasing area detection means. Therefore, the user can know the erasable data area in the loaded optical disk and, as the result, the user can specify a desired area to be erased.
According to a sixth aspect of the present invention, the optical disk data erasing apparatus according to the first or second aspect further comprises: a setting means with which the user sets, through the host computer, whether the interface bus is to be occupied or not during execution of the data erasing process; and a monitor means for monitoring the data erasing state on the basis of a state monitoring instruction which is periodically issued from the host computer, when it is set that the interface bus is not to be occupied; wherein the host computer is able to execute another process during execution of the data erasing process, when it is set that the interface bus is not to be occupied. Therefore, when the user sets that the interface bus is not to be occupied, the host computer can execute another process while the optical disk data erasing apparatus executes the data erasing process. Further, when the interface bus is to be occupied, the host computer can speedily detect the end of the erasing process of the optical disk data erasing apparatus.
According to a seventh aspect of the present invention, there is provided an optical disk data erasing apparatus which is an optical disk recording apparatus for writing or reading data in/from a recordable optical disk by irradiating the optical disk with a laser beam. The optical disk data erasing apparatus comprises: a first jumper switch setting means for setting ON/OFF of a first jumper switch; a setting identification means for identifying the setting of the first jumper switch; a judgement means for making a judgement as to whether a loaded optical disk is a write-once optical disk or not; an erasing means for overwriting the write-once optical disk by irradiating the optical disk with a laser beam having the same recording power as that at recording, according to the setting of the first jumper switch, thereby erasing data recorded on the optical disk; and an ejection means for automatically ejecting the optical disk after the data erasing process; wherein, when the first jumper switch is turned ON, the erasing means starts the data erasing operation; and when the first jumper switch is OFF or when the judgement means judges that the loaded optical disk is not a write-once optical disk, the ejection means automatically ejects the optical disk, and a display means displays that the data erasing process is not to be executed on the optical disk. Therefore, the optical disk data erasing process can be performed by the optical disk data erasing apparatus alone, according to an external control, without using the host computer. Further, since the data erasing process is automated, an optical disk data erasing apparatus capable of erasing recorded data completely is realized easily, at low cost, whereby leakage of secret information is prevented when the optical disk is discarded.
According to an eighth aspect of the present invention, there is provided an optical disk data erasing apparatus which is an optical disk recording apparatus for writing or reading data in/from a recordable optical disk by irradiating the optical disk with a laser beam. The optical disk data erasing apparatus comprises: a first jumper switch setting means for setting ON/OFF of a first jumper switch; a setting identification means for identifying the setting of the first jumper switch; a judgement means for making a judgement as to whether a loaded optical disk is a write-once optical disk or not; an erasing means for overwriting the write-once optical disk by irradiating the optical disk with a laser beam having a recording power higher than that at recording, according to the setting of the first jumper switch, thereby erasing the data recorded on the optical disk; and an ejection means for automatically ejecting the optical disk after the data erasing process; wherein, when the first jumper switch is turned ON, the erasing means starts the data erasing operation; and when the first jumper switch is OFF or when the judgement means judges that the loaded optical disk is not a write-once optical disk, the ejection means automatically ejects the optical disk, and display means displays that the data erasing process is not to be executed on the optical disk. Therefore, the optical disk data erasing process can be performed by the optical disk data erasing apparatus alone, according to an external control, without using the host computer. Further, since the data erasing process is automated, an optical disk data erasing apparatus capable of erasing recorded data completely is realized easily, at low cost, whereby leakage of secret information is prevented when the optical disk is discarded.
According to a ninth aspect of the present invention, the optical disk data erasing apparatus according to the seventh or eighth aspect further comprises a checking means for checking whether the data erasing process has normally ended or not; wherein, when the data erasing process for the write-once optical disk has not normally ended, the ejection means automatically ejects the optical disk, and the display means displays that the data erasing process had not been executed on the optical disk. Therefore, when the data erasing process has not ended normally, the loaded disk is automatically ejected, and the display means displays that the data erasing process has not been executed. Thereby, the user is prevented from recognizing that the erasing process has normally-ended, and from discarding the optical disk in which data to be erased has not been erased.
According to a tenth aspect of the present invention, the optical disk data erasing apparatus according to the ninth aspect further comprises a second jumper switch setting means for setting ON/OFF of a second jumper switch; wherein the setting identification means identifies the setting of the second jumper switch; when it is identified that the second jumper switch is ON, the erasing means executes the data erasing process over the entire surface of the optical disk; and when it is identified that the second jumper switch is OFF, the erasing means executes the data erasing process on a final session. Therefore, the user can select the erasing method according to the setting of the second jumper switch, and when there is no need to erase the data over the entire surface of the disk, the second jumper switch is turned off to prevent unnecessary entire-surface erasing from being executed. As the result, the time required for the erasing process is reduced, resulting in a low-cost optical disk data erasing apparatus.
According to an eleventh aspect of the present invention, the optical disk data erasing apparatus according to the seventh or eighth aspect further comprises a disk recording information acquisition means for acquiring information relating to a data-recorded area or a data-unrecorded area of the write-once optical disk; wherein the erasing means erases recorded data from the data-recorded area. Therefore, the data erasing process can be performed on only the data-recorded area, while the data-unrecorded area, which needs not be erased, is outside the target of the erasing process, whereby the time required for the erasing process is reduced.
According to a twelfth aspect of the present invention, the optical disk data erasing apparatus according to the eleventh aspect further comprises a determination means for determining whether data are recorded on the write-once optical disk or not, on the basis of the disk recording information obtained by the disk recording information acquisition means; wherein, when data are recorded on the write-once optical disk, the erasing means executes the recorded-data erasing process; and when no data are recorded on the write-once optical disk, the ejection means automatically ejects the optical disk, and the display means displays that the data erasing process is not to be executed on the optical disk. Therefore, when no data are recorded on the optical disk, the loaded disk is automatically ejected, and the display means displays that the data erasing process has not been executed, whereby the user knows that there is no need to execute the data erasing process, and performs the data erasing process on only a data-recorded optical disk, without performing an unnecessary erasing process.
According to a thirteenth aspect of the present invention, an optical disk data erasing method comprises: a judgement step of making a judgement as to whether a loaded optical disk is a write-once optical disk or not; an instruction recognition step of recognizing an instruction from a host computer; and a data erasing step of overwriting the optical disk which is judged as a write-once optical disk in the judgement step, by irradiating the optical disk with a laser beam having the same recording power as that at recording, on the basis of the instruction, thereby erasing data recorded on the optical disk. Therefore, data on an optical disk can be completely erased easily, at low cost, without having to use a special apparatus, and without generating substances detrimental to environment, whereby leakage of secret information can be prevented when the optical disk is discarded.
According to a fourteenth aspect of the present invention, an optical disk data erasing method comprises: a judgement step of making a judgement as to whether a loaded optical disk is a write-once optical disk or not; an instruction recognition step of recognizing an instruction from a host computer; and an erasing step of overwriting the optical disk which is judged as a write-once optical disk in the judgement step, by irradiating the optical disk with a laser beam having a recording power higher than that at recording, on the, basis of the instruction, thereby erasing data recorded on the optical disk. Therefore, data on an optical disk can be completely erased easily, at low cost, without having to use a special apparatus, and without generating substances detrimental to environment, whereby leakage of secret information can be prevented when the optical disk is discarded.
According to a fifteenth aspect of the present invention, the optical data erasing method according to the thirteenth or fourteenth aspect further comprises: a disk recording information acquisition instruction step of issuing a disk recording information acquisition instruction from the host computer; and a disk recording information acquisition step of acquiring information relating to a data-recorded area or a data-unrecorded area of the write-once optical disk, on the basis of the disk recording information acquisition instruction; wherein data recorded in the data-recorded area are erased in the erasing step. Therefore, the data erasing process can be performed on only the data-recorded area, while the data-unrecorded area, which needs not be erased, is outside the target of the erasing process, whereby the time required for the erasing process is reduced.
According to a sixteenth aspect of the present invention, the optical disk data erasing method according to the fifteenth aspect further comprises a determination step of determining whether data are recorded on the write-once optical disk or not, on the basis of the disk recording information which is obtained in the disk recording information acquisition step; wherein, when data are recorded on the write-once optical disk, the recorded data are erased in the erasing step; and when no data are recorded on the optical disk, an error signal is returned to the host computer in the determination step to notify the user that the data erasing process has not been executed on the optical disk. Therefore, when no data are recorded on the optical disk, the user can know that there is no need to execute the data erasing process on the disk, whereby the user can perform the erasing process on only a data-recorded optical disk, without performing an unnecessary erasing process.
According to a seventeenth aspect of the present invention, the optical disk data erasing method according to the fifteenth aspect further comprises: a notification step of notifying the user of the disk recording information which is obtained in the disk recording information acquisition step, through the host computer; an erasing area specification instruction step in which the user issues an instruction for specifying a data erasing area, on the basis of the disk recording information, through the host computer; and an erasing area detection step of detecting, from the data-recorded area obtained in the disk recording information acquisition step, an area corresponding to the specified erasing area on the basis of the instruction; wherein data recorded in the erasing area, which is detected by the erasing area detection means, are erased in the erasing step. Therefore, the user can know the erasable data area in the loaded optical disk and, as the result, the user can specify a desired area to be erased.
According to an eighteenth aspect of the present invention, the optical disk data erasing method according to the thirteenth or fourteenth aspect further comprises: a setting step in which the user sets, through the host computer, whether an interface bus is to be occupied or not during execution of the data erasing process; a monitoring instruction step of periodically issuing an erasing state monitoring instruction from the host computer, when it is set that the interface bus is not to be occupied; and a monitoring step of monitoring the data erasing state on the basis of the erasing state monitoring instruction. Therefore, when the user sets that the interface bus is not to be occupied, the host computer can execute another process while the optical disk data erasing apparatus executes the data erasing process. Further, when the interface bus is to be occupied, the host computer can speedily detect the end of the erasing process of the optical disk data erasing apparatus.
According to a nineteenth aspect of the present invention, an optical disk data erasing method comprises: a first jumper switch setting step of setting ON/OFF of a first jumper switch; a setting identification step of identifying the setting of the first jumper switch; a judgement step of making a judgement as to whether a loaded optical disk is a write-once optical disk or not; an erasing step of overwriting the write-once optical disk by irradiating the optical disk with a laser beam having the same recording power as that at recording, according to the setting of the first jumper switch, thereby erasing data recorded on the optical disk; and an ejection step of automatically ejecting the optical disk after the data erasing process; wherein, when the first jumper switch is ON, the erasing step starts the data erasing operation; and when the first jumper switch is OFF or when it is judged in the judgement step that the loaded optical disk is not a write-once optical disk, the optical disk is automatically ejected in the ejection step, and it is displayed, in a display step, that the data erasing process has not been executed on the optical disk. Therefore, the optical disk data erasing process can be performed by the optical disk data erasing apparatus alone, according to an external control, without using the host computer. Further, since the data erasing process is automated, recorded data can be completely erased easily, at low cost, whereby leakage of secret information is prevented when the optical disk is discarded.
According to a twentieth aspect of the present invention, an optical disk data erasing method comprises: a first jumper switch setting step of setting ON/OFF of a first jumper switch; a setting identification step of identifying the setting of the first jumper switch; a judgement step of making a judgement as to whether a loaded optical disk is a write-once optical disk or not; an erasing step of overwriting the write-once optical disk by irradiating the optical disk with a laser beam having a recording power higher than that at recording, according to the setting of the first jumper switch, thereby erasing data recorded on the optical disk; and an ejection step of automatically ejecting the optical disk after the data erasing process; wherein, when the first jumper switch is ON, the erasing step starts the erasing operation; and when the first jumper switch is OFF or when it is judged in the judgement step that the loaded optical disk is not a write-once optical disk, the optical disk is automatically ejected in the ejection step, and it is displayed, in a display step, that the data erasing process has not been executed on the optical disk. Therefore, the optical disk data erasing process can be performed by the optical disk data erasing apparatus alone, according to an external control, without using the host computer. Further, since the data erasing process is automated, recorded data can be completely erased easily, at low cost, whereby leakage of secret information is prevented when the optical disk is discarded.
According to a twenty-first aspect of the present invention, the optical disk data erasing method according to the nineteenth or twentieth aspect further comprises a checking step of checking whether the data erasing process has ended normally or not; wherein, when the data erasing process for the write-once optical disk has not ended normally, the optical disk is automatically ejected in the ejection step, and it is displayed, in the display step, that the data erasing process has not to been executed on the optical disk. Therefore, when the data erasing process has not ended normally, the loaded disk is automatically ejected, and it is displayed that the data erasing process has not been executed. Thereby, the user is prevented from recognizing that the erasing process has normally ended, and from discarding the optical disk in which data to be erased are not erased.
According to a twenty-second aspect of the present invention, the optical disk data erasing method according to the twenty-first aspect further comprises a second jumper switch setting step of setting ON/OFF of a second jumper switch; wherein the setting of the second jumper switch is identified in the setting identification step; when it is identified that the second jumper switch is ON, the data erasing process is executed over the entire surface of the optical disk in the erasing step; and when it is identified that the second jumper switch is OFF, the data erasing process is executed on a final session in the erasing step. Therefore, the user can select the erasing method according to the setting of the second jumper switch, and when there is no need to erase the data over the entire surface of the disk, the second jumper switch is turned off to prevent unnecessary entire-surface erasing from being executed. As the result, the time required for the erasing process is reduced, resulting in a low-cost optical disk data erasing apparatus.
According to a twenty-third aspect of the present invention, the optical disk data erasing method according to the nineteenth or twentieth aspect further comprises a disk recording information acquisition step of acquiring information relating to a data-recorded area or a data-unrecorded area of the write-once optical disk; wherein data recorded in the data-recorded area are erased in the erasing step. Therefore, the data erasing process can be performed on only the data-recorded area, while the data-unrecorded area, which needs not be erased, is outside the target of the erasing process, whereby the time required for the erasing process is reduced.
According to a twenty-fourth aspect of the present invention, the optical disk data erasing method according to the twenty-third aspect further comprises a determination step of determining whether data are recorded on the write-once optical disk or not, on the basis of the disk recording information obtained in the disk recording information acquisition step; wherein, when data are recorded on the write-once optical disk, the recorded data are erased in the erasing step; and when no data are recorded on the write-once optical disk, the optical disk is automatically ejected in the ejection step, and it is displayed, in the display step, that the data erasing process has not been executed on the optical disk. Therefore, when no data are recorded on the optical disk, the loaded disk is automatically ejected, and it is displayed that the data erasing process has not been executed, whereby the user knows that there is no need to execute the data erasing process, and performs the data erasing process on only a data-recorded optical disk, without performing an unnecessary erasing process.